In the information handling technology, the amount of information which can be processed at a given time is limited by various physical conditions. In a tape transport where magnetizable (more generally termed "magnetic") tape is passed from a supply reel past a recording and/or reproducing head to a takeup reel, the amount of information deposition or recall which occurs as the tape passes the head is a function of the tape speed. Accordingly various attempts have been made to increase the speed of tape movement from the supply reel to the takeup reel.
One approach to increasing tape speed includes shortening the route from the supply reel to the takeup reel. Instead of a longer path over tape guides, drive capstans and past the tape heads, it was found that a resilient capstan could be positioned between the supply and takeup reels, abutting the tape pack on the supply reel and also the tape pack on the takeup reel. It was also found that the tape could be moved very rapidly with this arrangement, without any supporting flanges for the tape packs on both reels. However various difficulties in such transports have prevented wide acceptance. One drawback is the requirement for a greater force between the takeup reel and capstan than the force present between the supply reel and the capstan. This difference in forces is necessary to maintain the appropriate tape tensions in the system and to keep the tape in its desired path. In general known solutions to the difference-in-forces problem have included support arrangements for biasing the supply and takeup reels toward the capstan, with some means to insure the bias force of the takeup reel exceeds that of the supply reel.
It is therefore a principal consideration of this invention to provide a tape transport capable of moving tape between the supply and takeup reels at a very high speed, of the order of 1,000 inches per second (ips) rather than 10 or 100 ips.
Another important consideration of the invention is the provision of such a tape transport with a substantially simplified arrangement for maintaining the requisite tape tensions and alignments in the system.